Celestron Ultima 9.25" Advanced Astro Master 3.40 Dave Ek's Digital Setting Circle USB BackyardEOS GP USB DEC Motor Canon 450D Modded Orion ShortTube 80-A Guide Scope DBK21 Guide Camera
George You know you're getting on when the equipment you farmed with is showing up as suburban lawn ornaments.
Quote:The tolerances between the baffle tube and the primary carrier are in the 0.0001 vicinity, but that's enough to allow the carrier to rock on the baffle tube. The grease is there to lube the mechanism, but more importantly to limit the rocking. If you OTA hasn't had it's primary out for a relube it's time. Grease is basically soap and oil. The oil evaporates over time. Folks recommend Dow Corning high vacuum grease, which is a synthetic (silicone) high viscosity grease. Sawbuck an ounch on eBay.
Uncle Rod Uncle Rod's Astroblog: http://uncle-rods.blogspot.com/
Quote:Lack of grease can be a problem with older OTAs, but be very cautious about regreasing. The grease on the baffle must be THIN. Too much and your problems escalate to focus drift. Too thick a layer and the mirror continues moving momentarily after you stop moving the focus control. NOT a good thing.
ROR Observatory Levenhuk 8" carbon fiber RC, Astro Physics CCDT67 Astro-Tech AT8IN w/Moonlite, Baader Mark III MPCC Levenhuk 80mm triplet, Astro Tech 0.8X reducer/flattener Celestron CGEM DX w/HyperTune STF-8300M SX 7 position 36mm CFW Astrodon 5nm H-alpha Little Piney Observatory
Warren - Stargazing since the 60's! Scopes: ETX-LS6, ED80T, AT6RC, Lunt LS60T, C9.25 Mounts: Atlas EQ-G, Vixen Portamount II Cameras: Atik 314L+,DMK31AU03,SSAG, ASI120MC Filters: Astrodon LRGB, Orion HA, SII, OIII Acc: Orion 5 place Filter wheels x 2, Flatman Primary Imaging site: Bortle Scale Class 6 Red Zone http://astrobin.com/users/rigel123/
"I like to watch"
Quote:But I am just a visual observer(Redundant?)
No materialistic vanity list to sport.
are we alone in the universe